Signal path in radio-frequency module having laminate substrate

ABSTRACT

Improved signal path in radio-frequency (RF) module having laminate substrate. In some embodiments, a laminate substrate for mounting RF components can include N conductor pads positioned at different layers of the laminate substrate. Such conductor pads can include an input pad, an output pad, and at least one intermediate pad between the input and output pads. The laminate substrate can further include a connection feature formed between each neighboring pair among the N conducting pads to provide a signal path between the input pad and the output pad. First and second connection features associated with each of the at least one intermediate pad can be positioned near opposite ends of the intermediate pad to thereby reduce parasitic effects associated with the N conductor pads. Examples of methods and devices related to such laminate substrate are disclosed.

BACKGROUND

1. Field

The present disclosure relates to improved signal path inradio-frequency (RF) module having laminate substrate.

2. Description of the Related Art

Many radio-frequency (RF) modules typically include one or morecomponents mounted on a laminate substrate. Such a laminate substratetypically includes a number of layers having conductive features thatare interconnected to provide, for example, a path for an RF signal.Such a path can introduce loss and/or noise to the RF signal.

SUMMARY

In accordance with some implementations, the present disclosure relatesto a laminate substrate for mounting radio-frequency (RF) components.The laminate substrate includes N conductor pads positioned at differentlayers of the laminate substrate and includes an input pad, an outputpad, and at least one intermediate pad between the input and outputpads. The laminate substrate further includes a connection featureformed between each neighboring pair among the N conducting pads toprovide a signal path between the input pad and the output pad. Firstand second connection features associated with each of the at least oneintermediate pad are positioned near opposite ends of the intermediatepad to thereby reduce parasitic effects associated with the N conductorpads.

In some embodiments, the quantity N can have a value that is greaterthan or equal to 4. In some embodiments, the signal path can be an inputsignal path or an output signal path for an RF component. The RFcomponent can include a low-noise amplifier (LNA).

In some embodiments, the connection feature can include one or morevias. The first and second connections features can be positioned at theopposite ends of the intermediate pad, with each of the opposite endsdefining an area sufficient to allow formation of the one or more vias.

In some embodiments, the laminate substrate can further include aninsulator layer disposed between each of the neighboring pair ofconducting pads. In some embodiments, each of the at least oneintermediate pad can have a reduced lateral dimension to facilitate thereduction in the parasitic effects associated with the N conductor pads.The different layers of the laminate substrate can further include otherconductor features about the N conductor pads. The reduced lateraldimension of each of the at least one intermediate pad results inreduction of parasitic effects between the N conductor pads and theother conductor features.

According to a number of implementations, the present disclosure relatesto a radio-frequency (RF) module that includes a laminate substrateconfigured to receive a plurality of components. The laminate substrateincludes N conductor pads positioned at different layers and includingan input pad, an output pad, and at least one intermediate pad betweenthe input and output pads. The laminate substrate further includes aconnection feature formed between each neighboring pair among the Nconducting pads to provide a signal path between the input pad and theoutput pad, with first and second connection features associated witheach of the at least one intermediate pad being positioned near oppositeends of the intermediate pad to thereby reduce parasitic effectsassociated with the N conductor pads. The RF module further includes anRF integrated circuit disposed on the laminate substrate. The RFintegrated circuit is connected to the output pad of the signal path.

In some embodiments, the RF integrated circuit can include a low-noiseamplifier (LNA). The reduced parasitic effects associated with the Nconductor pads can result in a reduced noise figure associated with theLNA. The output pad of the signal path can be connected to an input ofthe LNA. The RF module can further include a matching circuit disposedbetween the output pad of the signal path and the input of the LNA.

In some embodiments, the output pad of the signal path can be connectedto an output of the LNA. The RF module can further include a matchingcircuit disposed between the output of the LNA and the output pad of thesignal path. In some embodiments, the RF integrated circuit can beimplemented on a semiconductor die.

In some implementations, the present disclosure relates to a wirelessdevice that includes an antenna configured to receive a radio-frequency(RF) signal. The wireless device further includes a low-noise amplifier(LNA) module connected to the antenna. The LNA module includes an LNAconfigured to amplify the RF signal. The LNA module further includes alaminate substrate having a signal path for routing the RF signal to theLNA. The signal path includes N conductor pads positioned at differentlayers and includes an input pad, an output pad, and at least oneintermediate pad between the input and output pads. The signal pathfurther includes a connection feature formed between each neighboringpair among the N conducting pads to provide an electrical connectionbetween the input pad and the output pad. First and second connectionfeatures associated with each of the at least one intermediate pad arepositioned near opposite ends of the intermediate pad to thereby reduceparasitic effects associated with the N conductor pads and reduce anoise figure of the LNA. The wireless device further includes a receivercircuit connected to the LNA module. The receiver circuit is configuredto process the amplified RF signal received from the LNA module.

According to some teachings, the present disclosure relates to alaminate substrate for mounting radio-frequency (RF) components. Thelaminate substrate includes a plurality of conductor pads positioned atdifferent layers. The laminate substrate further includes a connectionfeature formed between each neighboring pair among the plurality ofconductor pads to provide a signal path between two end ones among theplurality of conductor pads. At least one of the plurality of conductorpads defines a cutout to reduce overlap between it and a neighboringconductor pad to thereby reduce parasitic effect associated with thesignal path.

In some embodiments, the signal path can be an input signal path or anoutput signal path for an RF component. The RF component can include alow-noise amplifier (LNA).

In some embodiments, the connection feature can include one or morevias. The plurality of conductor pads can include an input pad, anoutput pad, and at least one intermediate pad, with the input and outputpads being the two end pads of the signal path. The intermediate pad candefine the cutout. The intermediate pad can have an L shape, with thecutout being defined by the two legs of the L shape. Two legs of the Lshape can be dimensioned to support their respective vias extending inopposite directions.

In some embodiments, the laminate substrate can further include aninsulator layer disposed between each of the neighboring pair ofconductor pads. In some embodiments, each of the plurality of conductorpads can have a reduced lateral dimension to facilitate the reduction inthe parasitic effects associated with the signal path. The differentlayers of the laminate substrate can further include other conductorfeatures about the plurality of conductor pads. The reduced lateraldimension of each of the plurality of conductor pads can result inreduction of parasitic effects between the plurality of conductor padsand the other conductor features.

In a number of teachings, the present disclosure relates to aradio-frequency (RF) module that includes a laminate substrateconfigured to receive a plurality of components. The laminate substrateincludes a plurality of conductor pads positioned at different layers.The laminate substrate further includes a connection feature formedbetween each neighboring pair among the plurality of conductor pads toprovide a signal path between two end ones among the plurality ofconductor pads. At least one of the plurality of conductor pads definesa cutout to reduce overlap between it and a neighboring conductor pad tothereby reduce parasitic effect associated with the signal path. The RFmodule further includes an RF integrated circuit disposed on thelaminate substrate. The RF integrated circuit is connected to one of theend pads of the signal path.

In some embodiments, the RF integrated circuit can include a low-noiseamplifier (LNA). The reduced parasitic effects associated with theplurality of conductor pads can result in a reduced noise figureassociated with the LNA. The RF module can further include a matchingcircuit disposed between the signal path and an input of the LNA. Insome embodiments, the RF integrated circuit can be implemented on asemiconductor die.

In some implementations, the present disclosure relates to a wirelessdevice that includes an antenna configured to receive a radio-frequency(RF) signal. The wireless device further includes a low-noise amplifier(LNA) module connected to the antenna. The LNA module includes an LNAconfigured to amplify the RF signal. The LNA module further includes alaminate substrate having a signal path for routing the RF signal to theLNA. The signal path includes a plurality of conductor pads positionedat different layers. The signal path further includes a connectionfeature formed between each neighboring pair among the plurality ofconductor pads to electrically connect two end ones among the pluralityof conductor pads, with at least one of the plurality of conductor padsdefining a cutout to reduce overlap between it and a neighboringconductor pad to thereby reduce parasitic effect associated with thesignal path. The wireless device further includes a receiver circuitconnected to the LNA module. The receiver circuit is configured toprocess the amplified RF signal received from the LNA module.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the inventions have been described herein. It isto be understood that not necessarily all such advantages may beachieved in accordance with any particular embodiment of the invention.Thus, the invention may be embodied or carried out in a manner thatachieves or optimizes one advantage or group of advantages as taughtherein without necessarily achieving other advantages as may be taughtor suggested herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts a radio-frequency (RF) module having an RFpath configured to provide improved performance.

FIGS. 2A and 2B show that the RF module of FIG. 1 can be a low-noiseamplifier (LNA) module where one or more RF paths can provide reducednoise figure.

FIG. 3A shows an example of a laminate structure having multiple layersof conductive features.

FIG. 3B shows that some of the conductive features of FIG. 3A can beconfigured to provide an input path for an RF signal, and such a pathcan suffer from parasitic effects.

FIG. 4 schematically depicts a circuit that can represent the parasiticeffects associated with the input path of FIGS. 3A and 3B.

FIG. 5 shows an example of a modified input path that can be configuredto reduce parasitic effects and yield performance improvements such asreduction in noise figure.

FIG. 6 shows a side view of the input path configuration of FIG. 3B.

FIG. 7 shows a side view of the input path configuration of FIG. 5.

FIGS. 8A-8C show orientations of various conductor pads of the inputpath of FIG. 5 relative to other conductors in their respective layers.

FIG. 9 shows another example of a modified input path that can beconfigured to reduce parasitic effects and also yield a reducedfootprint size.

FIG. 10 shows examples of simulated noise figures (NF) for an LNA havinga current laminate (upper curve), and for an LNA having the modifiedlaminate (lower curve) configuration of FIG. 9.

FIG. 11 shows examples of measured noise figures (NF) for LNAs havingthe current laminate (upper curve) and the modified laminate (lowercurve) of FIG. 9 in an example frequency range of 1.4 to 2.4 GHz.

FIG. 12 shows examples of measured noise figures (NF) for LNAs havingthe current laminate (upper curve) and the modified laminate (lowercurve) of FIG. 9 in an example frequency range of 2.2 to 3.2 GHz.

FIG. 13 shows comparisons of various S-parameters for LNAs having thecurrent laminate and the modified laminate of FIG. 9.

FIG. 14 shows that in some embodiments, a module such as an LNA havingone or more features of the present disclosure can be implemented in awireless device.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

The headings provided herein, if any, are for convenience only and donot necessarily affect the scope or meaning of the claimed invention.

Described herein are various examples of a radio-frequency (RF) signalpath in a laminate module can be configured to provide desirableperformance features. FIG. 1 schematically depicts an RF module 100having a laminate substrate 102. For the purpose of description, it willbe understood that the laminate substrate 102 can include a plurality oflayers of conductor features separated by insulating material. In someembodiments, such layers of conductive features can be formed on theirrespective dielectric layers, and such dielectric layers can belaminated together to form the laminate substrate 102. Electricalconnections between the layers can be facilitated by, for example,conductive vias formed through the layers.

The laminate substrate 102 is shown to include an RF path 104 among theplurality of layers. In some embodiments, the RF path 104 can beconfigured to provide a pathway for an RF signal between an input(RF_IN) and an RF device 106. The RF device 106 can be configured toprocess the received RF signal and generate an output (RF_OUT).

Various examples of the RF path 104 are described herein in greaterdetail in the context of the foregoing input RF signals. It will beunderstood, however, that one of more features of the present disclosurecan also be implemented in other signal path applications. For example,one or more features as described herein can be implemented in signalpaths involving laminate layers and where reduction or control ofparasitic effects are desired.

FIGS. 2A and 2B show that in some embodiments, the module 100 of FIG. 1can be a low-noise amplifier (LNA) module 100. The LNA module 100 caninclude one or more RF paths 104, 104′ having one or more features asdescribed herein, and such RF paths can facilitate routing of RF signalsto and from an LNA 106. For example, and as shown in FIG. 2A, an RFsignal can be routed from an input (RF_IN) to an LNA 106 through the RFpath 104 and a matching/blocking circuit 110; and the amplified RFsignal from the LNA 106 can be routed to an output (RF_OUT) through amatching/blocking circuit 112 and the RF path 104′. As shown, the LNA106 can be biased by a bias circuit 114 (e.g., an active bias circuit).In some embodiments, and as shown in the example of FIG. 2B, the RF path104 can include one or more features as described herein at one or morelocations along the input side of the LNA 106. Similarly, one or morefeatures as described herein can also be implemented at one or morelocations on the output side of the LNA.

Various examples of the RF paths 104, 104′ are described herein ingreater detail in the context of the foregoing LNA module 100. It willbe understood, however, that one of more features of the presentdisclosure can also be implemented in other types of RF modules. Variousexamples of the RF paths are described herein in the context of input RFpaths; however, as shown in FIG. 2, other types of signal paths (e.g.,output RF path or an intermediate RF path) can also benefit from one ormore features of the present disclosure.

In the context of LNA modules, one or more features of the presentdisclosure can be implemented for different types of LNAs. For example,LNAs based on gallium arsenide (GaAs) process technology andsilicon-on-insulator (SOI) process technology can benefit from use of RFpaths as described herein.

FIG. 3A shows an example laminate configuration 10 having four layers(12, 14, 16, 18) of conductors, including conductor pads (22, 24, 26,28) for an RF signal path 20 that can be utilized as an input. Althoughdescribed in the context of four example layers, it will be understoodthat other numbers of layers can also be utilized. For example, laminateconfigurations having 2, 3, 4, 5, or higher number of layers can benefitfrom one or more features described herein.

FIG. 3B shows an enlarged view of the signal path 20 formed between thefirst pad 22 (where input signal RFIN is received) and the fourth pad 28(which is connected to an input matching component of an LNA (notshown)). The first pad 22 is shown to be electrically connected to thesecond pad 24 through conductive vias 33; the second pad 24 is shown tobe electrically connected to the third pad 26 through conductive vias35; and the third pad 26 is shown to be electrically connected to thefourth pad 28 through conductive vias 37.

In the example of FIG. 3B, parasitic effects such as parasiticcapacitance can result due to the pads being in proximity to each otheras well as other conductive features in their respective layers. Forexample, parasitic capacitance can be present between the first andsecond pads (22, 24), between the second and third pads (24, 26),between the third and fourth pads (26, 28). Parasitic capacitance canalso be present between a given pad and other conductor feature(s) inthe same layer. Each of the first and third pads (22, 26) and itsrespective nearby conductor are shown to yield parasitic capacitance.The second and fourth pads (24, 28) can also yield such parasiticcapacitances. Although described in the context of parasiticcapacitance, it will be understood that other effects can alsocontribute to the parasitic effects. For example, due to conductive padsat different layers, parasitic inductances and resistances can bepresent in a given RF path. Such parasitic capacitance, inductance andresistance can collectively form an unwanted series of parasiticelements in the RF path.

FIG. 4 schematically shows that the foregoing parasitic effectsassociated with the signal path 20 can be represented by a parasiticcircuit 40 having a resistance 42, an inductance 44, and a capacitance46. As is generally understood, such parasitic effects can result indegradation of an RF signal to yield, for example, an increase in noisefigure (NF) and/or RF loss. If the parasitic effect is sufficientlylarge (e.g., depending on the number of pads and layers), the parasiticcircuit 40 can contribute significantly to, for example, thematching/blocking circuits 110, 112 described herein in reference toFIG. 2. Although the example parasitic circuit 40 in FIG. 4 is depictedas a simple series/parallel representation, it will be understood thatthe circuit may contain more passive elements that are represented herecollectively in the simplified circuit 40. It will also be understoodthat while various examples are described herein in the context of noisefigure problems and improvements, one or more features of the presentdisclosure can address and improve performance associated with RF lossand/or other issues related to parasitic effects.

FIG. 5 shows an example of a modified signal path 104 that can beconfigured to reduce the parasitic effects, and thereby improve thenoise figure performance. Similar to the example of FIG. 3B, themodified signal path 104 is described in the context of four layers. Itwill be understood, however, one or more features as described hereincan be implemented in laminate devices having more or less number oflayers.

In the example shown in FIG. 5, the signal path 104 is formed between afirst pad 122 (where input signal RFIN is received) and a fourth pad 128(which is connected to an input of an LNA (not shown)). The first pad122 is shown to be electrically connected to a second pad 124 throughconductive vias 133; the second pad 124 is shown to be electricallyconnected to a third pad 126 through conductive vias 135; and the thirdpad 126 is shown to be electrically connected to the fourth pad 128through conductive vias 137.

Differences between the foregoing modified signal path 104 of FIG. 5 andthe signal path 20 of FIG. 3B are depicted in FIGS. 6 and 7. FIG. 6shows a side view of the signal path 20 of FIG. 3B, and FIG. 7 shows aside view of the modified signal path 104 of FIG. 5. For the purpose ofdescription, the conductive features about the pads at different layersof the examples of FIGS. 3B and 5 can remain generally the same (e.g.,to provide comparison in performance between the two configurations).However, it will be understood that the modified signal path 104 of FIG.5 is not required to have similar nearby conductors as those associatedwith the signal path 20 of FIG. 3B.

As shown, the pads of the modified signal path 104 are dimensioned andarranged so that an overlap between a pair of vertically neighboringpads overlap significantly less than that of the corresponding pair ofpads of the signal path 20. For example, the left edge (indicated byline 43) of the first pad 22 in FIG. 6 is shown to extend approximatelyto a midpoint of the second pad 24 and overlap with at least a portionof the via 35. In contrast, the left edge (indicated by line 143) of thefirst pad 122 in FIG. 7 is shown to extend significantly less to therebysignificantly reduce the amount of overlap between the first and secondpads 122, 124. The left edge 143 of the first pad 122 is also shown tonot overlap with the via 135.

In another example, the left edge (indicated by line 45) of the secondpad 24 in FIG. 6 is shown to extend approximately to the left edge ofthe third pad 26 and overlap with the via 37. Similarly, the right edge(indicated by line 49) of the third pad 26 in FIG. 6 is shown to extendapproximately to the right edge of the second pad 24 and overlap withthe via 33. In contrast, the left edge (indicated by line 145) of thesecond pad 124 and the right edge (indicated by line 149) of the thirdpad 126 in FIG. 7 are shown to extend significantly less to therebysignificantly reduce the amount of overlap between the second and thirdpads 124, 126. The left edge 145 of the second pad 124 is shown to notoverlap with the via 137, and the right edge 149 of the third pad 126 isshown to not overlap with the via 133.

In yet another example, the right edge (indicated by line 47) of thefourth pad 28 in FIG. 6 is shown to extend approximately to a midpointof the third pad 26 and overlap with the via 35. In contrast, the rightedge (indicated by line 147) of the fourth pad 128 in FIG. 7 is shown toextend significantly less to thereby significantly reduce the amount ofoverlap between the fourth and third pads 128, 126. The right edge 147of the fourth pad 128 is also shown to not overlap with the via 135.

In some embodiments the foregoing reduced overlaps between neighboringpads in the example signal path 104 can be achieved by dimensioning theneighboring pads so that their overlapping portions are generallylimited by one or more parameters. For example, the first pad 122 actingas an input contact pad for an input RF signal from outside of themodule may be required to have a minimum surface area per a designspecification. Accordingly, the first pad 122 can have its area reducedto approximately such a minimum area to thereby reduce the amount ofoverlap with the second pad 124. In some embodiments, the foregoingreduced area of the first pad 122 can allow the area of the pad to beshifted laterally and still be within the design specification. Thus, inthe example shown, the first pad 122 is shown to be shifted slightly tothe right side, thereby further reducing the amount of overlap with thesecond pad 124.

The second pad 124 can also be configured to reduce its overlap with thefirst pad 122. For example, the right side of the pad 124 can beconfigured to extend sufficiently to facilitate effective connectionwith the via 133, but not extend significantly further to reduce theamount of overlap on the right side of the via 133.

The left side of the second pad 124 can also be configured to extendsufficiently to facilitate effective connection with the via 135, butnot extend significantly further. Similarly, the right side of the thirdpad 126 can also be configured to extend sufficiently to facilitateeffective connection with the via 135, but not extend significantlyfurther. Such configurations of the second and third pads 124, 126 canallow electrical connections between the two pads with reduced orminimized overlap.

The fourth pad 128 can function as an output pad of the signal path 104,and is shown to be connected to the via 137. In some embodiments, thefourth pad 128 can be dimensioned so that its left and right sidesextend sufficiently to facilitate effective connection with the via 137,but not extend significantly further. Such a configuration of the fourthpad 128 can allow its electrical connection with the third pad 126 withreduced or minimized overlap.

In the foregoing example, the first pad 122 has lateral dimensions ofapproximately 250 μm×250 μm which is or close to a minimum area neededto hold the vias. Each of the vias has a diameter of about 230 m indiameter. Pad sizes in different layers can vary with the routing of thesignal from the input (e.g., bottom-most pad) to the output (e.g.,top-most pad). In some embodiments, such pad sizes can be based on twoconditions: (1) Minimize or reduce pad size at each layer but sufficientenough to accommodate signal routing via(s), and (2) Minimize or reduceoverlap between two neighboring pads.

FIGS. 8A-8C show the first, second, and third pads 122, 124, 126 of the4-layer example described herein in reference to FIG. 7. Such pads areshown relative to other portions of their respective conductive layers12, 14, 16. For the purpose of description of FIGS. 8A-8C, it will beassumed that such other portions of the conductive layers 12, 14, 16 canremain substantially the same as those associated with the signal path20 of FIGS. 3A, 3B, and 6 to, for example, demonstrate additionaladvantages that can be obtained from the reduced-overlap examples ofFIGS. 5 and 7. It will be understood, however, that such other portionsof the conductive layers 12, 14, 16 can also be modified to yield adesired performance with the modified the modified pads 122, 124, 126.It will also be understood that one or more features associated with theconductive layers 12, 14, 16 can also be implemented in the fourthconductive layer 18.

In FIG. 8A, the first pad 122 as described in reference to FIG. 7 isshown to yield gaps d1 and d3 along the Y-direction, and d2 along theX-direction. Each of the gaps d1, d2 and d3 can be increased from theunmodified configuration of FIG. 6 to thereby reduce the parasiticcoupling between the corresponding edge of the pad 122 and the edge itfaces.

In FIG. 8B, the second pad 124 as described in reference to FIG. 7 isshown to yield gaps d4 and d6 along the Y-direction, and d5 along theX-direction. The gap d4 is increased significantly from the unmodifiedconfiguration of FIG. 6 to thereby reduce the parasitic coupling betweenthe corresponding edge of the pad 124 and the edge it faces. In theexample shown, each of the gaps d6 and d5 can also be increased tothereby reduce the parasitic coupling between the corresponding edge ofthe pad 124 and the edge it faces.

In FIG. 8C, the third pad 126 as described in reference to FIG. 7 isshown to yield gaps d7 and d9 along the Y-direction, and d8 along theX-direction. The gap d9 is increased significantly from the unmodifiedconfiguration of FIG. 6 to thereby reduce the parasitic coupling betweenthe corresponding edge of the pad 126 and the edge it faces. In theexample shown, each of the gaps d7 and d8 can also be increased tothereby reduce the parasitic coupling between the corresponding edge ofthe pad 126 and the edge it faces.

FIG. 9 shows another example of a modified signal path 104 that can beconfigured to reduce the parasitic effects, and to provide a reducedfootprint. Similar to the other examples described herein, the modifiedsignal path 104 is described in the context of four layers. It will beunderstood, however, one or more features as described herein can beimplemented in laminate devices having more or less number of layers.

In the example shown in FIG. 9, the signal path 104 is formed between afirst pad 222 (where input signal RF_IN is received) and a fourth pad228 (which is connected to an input matching circuit of an LNA (notshown)). The first pad 222 is shown to be electrically connected to asecond pad 224 through a conductive via 233; the second pad 224 is shownto be electrically connected to a third pad 226 through a conductive via235; and the third pad 226 is shown to be electrically connected to thefourth pad 228 through conductive vias 237.

In the example signal path 104 of FIG. 9, the four pads 222, 224, 226,228 are shown to be stacked closer to each other when viewed from thetop, thereby reducing the overall footprint taken up by the signal path104. To accommodate such a reduced footprint, rectangular areascorresponding to the four pads 222, 224, 226, 228 generally overlap witheach other. However, by applying one or more of the design criteria asdescribed herein to some or all of the four pads 222, 224, 226, 228, thesignal path 104 can be configured to yield reduced parasitics among thepads as well as with the surrounding conductors, to thereby reduce thenoise figure of the LNA.

The first pad 222 is shown to have reduced lateral dimensions so as toincrease the gaps d11 and d12 between two of its edges with thecorresponding edges on the surrounding conductor to thereby reduceparasitic effects. The reduced size of the first pad 222 is also shownto reduce the amount of overlap with the second pad 224 which has an Lshape that defines a cutout 244. Thus, the first pad 222 overlaps withonly a portion (e.g., area sufficient to support the via 233) of one ofthe legs of the L-shaped pad 224. The cutout 244 also generallyincreases the gap between the edges of the cutout and the correspondingedge on the surrounding conductor, thereby reducing the parasiticeffects. The second pad 224 can also be dimensioned so as to increasethe gap dimension d13 to further reduce the parasitic effects.

The amount of overlap between the second and third pads 224, 226 isshown to be reduced by the cutout 244 in the second pad 224. Thus, onecan see that the second pad 224 is shaped and dimensioned to support thetwo vias 233 and 235 and to provide electrical connections therebetween.The example L shape allows such vias to be arranged in a more flexiblemanner.

The third pad 226 can have reduced lateral dimensions so as to increasethe gaps between two of its edges and the corresponding edges of thesurrounding conductor, thereby further reducing the parasitic effects.The third pad 226 and the fourth pad 228 are shown to overlapsignificantly. However, the actual overlapped area can be reduced by thereduced sizes of the two pads 226, 228. In the example shown, the outerportions of the third and fourth pads 226, 228 are shown to bedimensioned sufficiently to support the two vias 237. The inner side ofthe third pad 226 is shown to extend only enough to support the via 235between it and the second pad 224.

FIGS. 10-12 show examples of improvements in performance that can beobtained for an LNA module having the signal path 104 as describedherein in reference to FIG. 9. Similar performance improvements can beobtained for the examples described in reference to FIGS. 5 and 5. Forthe purpose of comparisons in FIGS. 10-12, such a modified configurationof FIG. 9 is also referred to as a “modified laminate,” and theunmodified configuration of FIGS. 4 and 6 is also referred to as a“current laminate.”

FIG. 10 shows plots of simulated noise figures (NF) for an LNA having acurrent laminate (upper curve), and for an LNA having a modifiedlaminate (lower curve) as described herein. Several samples of measureddata points at “m2,” “m3,” and “m4” for the current laminate and “m14,”“m13,” and “m12” for the modified laminate are indicated in FIG. 10, andalso listed in Table 1.

TABLE 1 Frequency NF (Current) NF (Modified) NF_(current)-NF_(modified)1.6 GHz 0.492 dB (m2) 0.458 dB (m14) 0.034 dB 1.9 GHz 0.586 dB (m3)0.539 dB (m13) 0.047 dB 2.2 GHz 0.873 dB (m4) 0.766 dB (m12) 0.107 dB

FIG. 11 shows plots of measured noise figures (NF) for the LNA of FIG.10 having a current laminate (upper curve), and for the LNA of FIG. 10having a modified laminate (lower curve) as described herein. Table 2lists reductions in noise figure (NF_(current)−NF_(modified)) atdifferent frequencies in a range of 1.4 to 2.3 GHz.

TABLE 2 Frequency Reduction in noise figure (NF_(current)-NF_(modified)) 1.4 GHz 0.12 dB 1.45 GHz  0.1 dB 1.55 GHz 0.05 dB  1.6 GHz 0.07 dB 1.65GHz 0.05 dB  1.7 GHz 0.03 dB  1.8 GHz 0.04 dB  1.9 GHz 0.06 dB 1.95 GHz0.06 dB  2.1 GHz  0.1 dB 2.15 GHz 0.11 dB  2.2 GHz 0.14 dB 2.25 GHz 0.17dB  2.4 GHz 0.21 dB

As seen in FIG. 11 and in Table 2, reductions in measured noise figuresare significant in the example frequency range of 1.4 to 2.4 GHz. Insome applications, an additional improvement of about 0.05 dB can beobtained over the example of Table 2, by implementing one or morefeatures as described herein at one or more locations along the RF pathassociated with the LNA.

FIG. 12 shows that such significant reductions in noise figure can alsobe obtained in other frequencies. In FIG. 12, the upper curvecorresponds to a plot of measured noise figure for another LNA having acurrent laminate as described herein. The lower curve corresponds to aplot of measured noise figure for another LNA having a modified laminateas described herein. Table 3 lists reductions in noise figure(NF_(current)−NF_(modified)) at different frequencies in a range of 2.2to 3.2 GHz.

TABLE 3 Frequency Reduction in noise figure (NF_(current)-NF_(modified)) 2.2 GHz 0.08 dB 2.25 GHz 0.07 dB  2.3 GHz 0.07 dB  2.6 GHz 0.11 dB 2.65GHz  0.1 dB  2.7 GHz 0.09 dB 2.75 GHz 0.12 dB  2.8 GHz 0.17 dB 2.85 GHz0.13 dB  2.9 GHz 0.17 dB 2.95 GHz 0.16 dB  3.0 GHz  0.2 dB 3.05 GHz 0.22dB  3.1 GHz 0.31 dB 3.15 GHz 0.31 dB  3.2 GHz 0.41 dB

In some situations, an improvement in performance in one area can beachieved at the expense of performance degradation in another area. Inthe examples described in reference to FIGS. 10-12, the improvements innoise figures can be achieved without degrading performance in otherareas. FIG. 13 show examples of how performance related to S-parametersremain generally the same between the current laminate configuration andthe modified laminate configuration (FIG. 9). The example S-parametercomparisons shown in FIG. 13 are for a relatively small RF signal. Alarge RF signal also yields similar results where S-parameterperformance does not differ significantly between the current andmodified laminate configurations.

In the various examples described herein, it is generally desirable toreduce parasitic effects associated with signal paths in laminatelayers. Such reduction in parasitic effects can be achieved by, forexample, reducing sizes of the pads associated with such laminate layersto thereby reduce overlaps among the pads and to increase edge-to-edgedistances between the pads and other conductive features on theirrespective layers.

In some situations, some controllable amount of parasitic effects may bedesirable. As described herein, parasitic effects can be controlled insome quantifiable manner. Thus, it will be understood that one or morefeatures described herein can be implemented to control parasiticeffects associated with signal paths in laminate layers. Such a controlcan include controlled reduction or increase of parasitic effects.

In some implementations, a device and/or a circuit having one or morefeatures described herein can be included in an RF device such as awireless device. Such a device and/or a circuit can be implementeddirectly in the wireless device, in a modular form as described herein,or in some combination thereof. In some embodiments, such a wirelessdevice can include, for example, a base station configured to providewireless services, a cellular phone, a smart-phone, a hand-held wirelessdevice with or without phone functionality, a wireless tablet, etc.

FIG. 14 schematically depicts an example wireless device 400 having oneor more advantageous features described herein. In the context of signalpaths as described herein, an RF module such as an LNA module 100 caninclude one or more LNAs 106 and one or more signal paths (e.g., 104,104′). The signal path 104 can receive RF signals from an antenna 424through a front-end switch 422 and a duplex circuit 420 (e.g., for afrequency-division duplexing (FDD) configuration; for a time-divisionduplexing (TDD) configuration, the duplexers can be replaced with passfilters) and provide the signals to the LNAs 106. The signal path 104′can route the amplified signals from the LNAs 106 to outputs of the LNAmodule 100. In some embodiments, one or more of the LNAs 106 can beimplemented in a semiconductor die. Such a die can be mounted on alaminate substrate having one or more signal paths having one or morefeatures described herein.

In the example wireless device 400, a power amplifier (PA) 300 having aplurality of amplification paths can provide an amplified RF signal tothe switch 422 (via the duplexer 420), and the switch 422 can route theamplified RF signal to the antenna 424. The PA 300 can receive anunamplified RF signal from a transceiver 414.

The transceiver 414 is shown to interact with a baseband sub-system 410that is configured to provide conversion between data and/or voicesignals suitable for a user and RF signals suitable for the transceiver414. The transceiver 414 is also shown to be connected to a powermanagement component 406 that is configured to manage power for theoperation of the wireless device 400.

The baseband sub-system 410 is shown to be connected to a user interface402 to facilitate various input and output of voice and/or data providedto and received from the user. The baseband sub-system 410 can also beconnected to a memory 404 that is configured to store data and/orinstructions to facilitate the operation of the wireless device, and/orto provide storage of information for the user.

A number of other wireless device configurations can utilize one or morefeatures described herein. For example, a wireless device does not needto be a multi-band device. In another example, a wireless device caninclude additional antennas such as diversity antenna, and additionalconnectivity features such as Wi-Fi, Bluetooth, and GPS.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The word “coupled”, as generally usedherein, refers to two or more elements that may be either directlyconnected, or connected by way of one or more intermediate elements.Additionally, the words “herein,” “above,” “below,” and words of similarimport, when used in this application, shall refer to this applicationas a whole and not to any particular portions of this application. Wherethe context permits, words in the above Detailed Description using thesingular or plural number may also include the plural or singular numberrespectively. The word “or” in reference to a list of two or more items,that word covers all of the following interpretations of the word: anyof the items in the list, all of the items in the list, and anycombination of the items in the list.

The above detailed description of embodiments of the invention is notintended to be exhaustive or to limit the invention to the precise formdisclosed above. While specific embodiments of, and examples for, theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. For example, whileprocesses or blocks are presented in a given order, alternativeembodiments may perform routines having steps, or employ systems havingblocks, in a different order, and some processes or blocks may bedeleted, moved, added, subdivided, combined, and/or modified. Each ofthese processes or blocks may be implemented in a variety of differentways. Also, while processes or blocks are at times shown as beingperformed in series, these processes or blocks may instead be performedin parallel, or may be performed at different times.

The teachings of the invention provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

While some embodiments of the inventions have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. A laminate substrate for mounting radio-frequency(RF) components, the laminate substrate comprising: N conductor padspositioned at different layers of the laminate substrate and includingan input pad, an output pad, and at least one intermediate pad betweenthe input and output pads; and a connection feature formed between eachneighboring pair among the N conducting pads to provide a signal pathbetween the input pad and the output pad, first and second connectionfeatures associated with each of the at least one intermediate pad beingpositioned near opposite ends of the intermediate pad to thereby reduceparasitic effects associated with the N conductor pads.
 2. The laminatesubstrate of claim 1 wherein the quantity N has a value that is greaterthan or equal to
 4. 3. The laminate substrate of claim 1 wherein thesignal path is an input signal path or an output signal path for an RFcomponent.
 4. The laminate substrate of claim 3 wherein the RF componentincludes a low-noise amplifier (LNA).
 5. The laminate substrate of claim1 wherein the connection feature includes one or more vias.
 6. Thelaminate substrate of claim 1 wherein the first and second connectionsfeatures are positioned at the opposite ends of the intermediate pad,each of the opposite ends defining an area sufficient to allow formationof the one or more vias.
 7. The laminate substrate of claim 1 furthercomprising an insulator layer disposed between each of the neighboringpair of conducting pads.
 8. The laminate substrate of claim 1 whereineach of the at least one intermediate pad has a reduced lateraldimension to facilitate the reduction in the parasitic effectsassociated with the N conductor pads.
 9. The laminate substrate of claim8 wherein the different layers of the laminate substrate further includeother conductor features about the N conductor pads, the reduced lateraldimension of each of the at least one intermediate pad resulting inreduction of parasitic effects between the N conductor pads and theother conductor features.
 10. The laminate substrate of claim 1 whereinat least one of the N conductor pads defines a cutout to reduce overlapbetween it and a neighboring conductor pad to thereby reduce parasiticeffect associated with the signal path.
 11. A radio-frequency (RF)module, comprising: a laminate substrate configured to receive aplurality of components, the laminate substrate including N conductorpads positioned at different layers and including an input pad, anoutput pad, and at least one intermediate pad between the input andoutput pads, the laminate substrate further including a connectionfeature formed between each neighboring pair among the N conducting padsto provide a signal path between the input pad and the output pad, firstand second connection features associated with each of the at least oneintermediate pad being positioned near opposite ends of the intermediatepad to thereby reduce parasitic effects associated with the N conductorpads; and an RF integrated circuit disposed on the laminate substrate,the RF integrated circuit connected to the output pad of the signalpath.
 12. The module of claim 11 wherein the RF integrated circuitincludes a low-noise amplifier (LNA).
 13. The module of claim 12 whereinthe reduced parasitic effects associated with the N conductor padsresult in a reduced noise figure associated with the LNA.
 14. The moduleof claim 12 wherein the output pad of the signal path is connected to aninput of the LNA.
 15. The module of claim 14 further comprising amatching circuit disposed between the output pad of the signal path andthe input of the LNA.
 16. The module of claim 12 wherein the output padof the signal path is connected to an output of the LNA.
 17. The moduleof claim 16 further comprising a matching circuit disposed between theoutput of the LNA and the output pad of the signal path.
 18. The moduleof claim 11 wherein the RF integrated circuit is implemented on asemiconductor die.
 19. The module of claim 11 wherein at least one ofthe N conductor pads defines a cutout to reduce overlap between it and aneighboring conductor pad to thereby reduce parasitic effect associatedwith the signal path.
 20. A wireless device, comprising: an antennaconfigured to receive a radio-frequency (RF) signal; a low-noiseamplifier (LNA) module connected to the antenna, the LNA moduleincluding an LNA configured to amplify the RF signal, the LNA modulefurther including a laminate substrate having a signal path for routingthe RF signal to the LNA, the signal path including N conductor padspositioned at different layers and including an input pad, an outputpad, and at least one intermediate pad between the input and outputpads, the signal path further including a connection feature formedbetween each neighboring pair among the N conducting pads to provide anelectrical connection between the input pad and the output pad, firstand second connection features associated with each of the at least oneintermediate pad being positioned near opposite ends of the intermediatepad to thereby reduce parasitic effects associated with the N conductorpads and reduce a noise figure of the LNA; and a receiver circuitconnected to the LNA module, the receiver circuit configured to processthe amplified RF signal received from the LNA module.